Convertible bonds are a bit tricky. They are actually both debt and equity. The fact that they can be (sometimes it’s certain) converted in equity makes these bonds to have a debt and also an equity element. So the short answer is that are both debt and equity.
Another question is how to find what is the equity and what is debt element of this bond! The calculation is a bit complicated so if you need it, I could write an example.
Convertible bonds are both equity and debt. They have a debt element and an equity element. You will need to calculate the present value of the coupon payments plus the redemption value and discount it by using a rate that a bond that does not have the conversion offers. The difference between this present value and the current market value is the equity. The remaining is the debt.